1. Field of the Invention
The present invention relates to a system for protecting copyright of content which is a work. More particularly, the present invention relates to a work protection technology in a content distribution system which distributes content which is a work.
2. Description of the Related Art
In recent years, as high speed access lines become widespread and internet technologies develop, content distribution services are being realized in which content such as images and music are distributed via the Internet. In order to popularize the content distribution services, it is indispensable that a proper consideration is paid to an owner of the content. For this purpose, a system which bills a user of the content becomes necessary.
For example, Japanese laid-open patent application No.2000-101573 discloses a content distribution system which bills a user according to usage of content. In the content distribution system disclosed in the Japanese laid-open patent application No.2000-101573, a server performs a content distribution process according to a request from a content receiving terminal, and the server performs a billing process for content usage.
In a large-scale content distribution system which is used by many users, when user authentication, billing process and content distribution process are performed by the same server, load for performing these processes becomes too large so that there occurs a problem in that the number of users to which content can be simultaneously distributed is decreased.
Therefore, it becomes necessary that the user authentication, the billing process and the content distribution process are performed by respective servers in order to realize load distribution. In addition, by realizing load distribution, it becomes possible that billing for the content owner and billing for the content user can be performed by different billing operators respectively so that various content distribution services become available.